Abstract: Allometric relationship (LA = aL W , where a, b and c are the parameters) was fitted between bc the true leaf area and extreme linear measurements viz. length and width of groundnut (Arachis hypogeae L.) leaves to obtain the total leaf area without having to make the time-consuming area measurements directly. Groundnut (var. CO2) was raised at Coconut research station, Aliyar Nagar, Tamil Nadu Agricultural University, Coimbatore from which one hundred and twenty seven leaves were randomly selected at flowering stage. The allometric relationship between true leaf area and extreme linear measurements were fitted by ordinary least square (OLS) method. The predicted allometric model for the leaf area of groundnut was TLAm = 0.8955 L W . Also, using the same extreme linear 1.0842 0.7569 measurements and true leaf area, average 'K' factor was determined as 0.821 to use in the estimation of leaf area by using the formula TLAm = k * L * W. Both the model's predictability was tested for their validity using R and chi square tests. The allometric model fitted well to predict the true leaf area by 94%.
